Mitt Romney's choice of Paul Ryan as his running mate has already reignited the debate over the future of Medicare. Ryan has proposed ending the guaranteed benefit and instead giving individuals vouchers to pay for private insurance, which Ryan refers to as "premium support." By reducing the amount of money that Medicare would pay out over time, the plan reduces its long-term costs in an effort to become solvent without raising taxes or lowering health care costs. But it leaves seniors on the hook should costs rise faster than the value of the vouchers.

It's a proposal strikingly similar to his suggested Social Security reform in 2005, which also relied on shifting risk from society at large to the individual.

Ryan, in a March 2005 interview on C-SPAN, described his Social Security plan in detail. His bill would have allowed people under 55 to divert roughly half of their payroll taxes away from the traditional program and into a private account "owned" by the individual but managed by Social Security, and invested in stocks and bonds. But that plan did not cut any benefits, but brought such an astronomical price tag that the Bush administration called it "irresponsible."